(1) Field of the Invention
The present invention related to display devices, and more particularly to a device which obtains three-dimensional images by using two liquid crystal panels.
(2) Description of the Related Art
One of the known methods of displaying a three-dimensional image is to arrange transmissive display panels with spacing between them, form similar images on the two transmissive display panels and control the luminance levels of the two images to create a sense of depth and thereby form a three-dimensional image. Technical literature disclosing such a method includes Japanese Patent Application Laid-Open Publication No. 2001-54144. A typical transmissive display device of this kind is a liquid crystal display panel.
In a liquid crystal display panel, many scanning lines and video signal lines are arranged crossing one another, and pixels are formed in areas surrounded by scanning lines and video signal lines. Therefore, a microscopic look at its screen would reveal regular occurrence of brighter parts and darker parts. When two liquid crystal display panels are arranged at a distance in mutually overlapping positions and images are formed, the brighter parts and the darker parts regularly formed on each liquid crystal display panel interfere with other to give rise to so-called moirés. Arrangement of a light diffusing layer between the two liquid crystal panels to address the problem of moiré occurrence in such a configuration is described in Japanese Patent No. 3335998.
By arranging a light diffusing layer between the two liquid crystal display panels as stated in Japanese Patent No. 3335998, moirés can be reduced, but there are such side effects as a drop in front luminance level, a decrease in contrast and blurring of images (fuzzy image contours).
An object of the present invention is to provide a display device in which three-dimensional images are obtained by arranging two liquid crystal display panels at a distance and controlling image signals of the two liquid crystal panels and which reduces moirés occurring as described above and prevents such side effects as a drop in front luminance level, a decrease in contrast and blurring of images.